The best way too determine if you have a leak in your plumbing system, is by first checking your water meter.

If you do not know where your meter is located you can call your local building deportment to get your meter location.

Make sure no water is being used inside or outside of your house.

Locate your water meter and check the leak indicator to see if it is moving. Depending on the brand of your meter, the leak indicator could be a small triangular shaped dial or a small silver wheel that rotates when water is flowing through the meter. If the dial is moving, chances are, you have a leak.

Or, you can also take a meter reading and wait 1 or 2 hours and take another meter reading (make sure no water is used during this time). If the reading has changed, you have a leak.